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qmk_firmware

custom branch of QMK firmware git clone https://anongit.hacktivis.me/git/qmk_firmware.git

audio_pwm_hardware.c (11170B)

    

  1. /* Copyright 2016 Jack Humbert
  2.  * Copyright 2020 JohSchneider
  3.  *
  4.  * This program is free software: you can redistribute it and/or modify
  5.  * it under the terms of the GNU General Public License as published by
  6.  * the Free Software Foundation, either version 2 of the License, or
  7.  * (at your option) any later version.
  8.  *
  9.  * This program is distributed in the hope that it will be useful,
  10.  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12.  * GNU General Public License for more details.
  13.  *
  14.  * You should have received a copy of the GNU General Public License
  15.  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16.  */
  18. #include "audio.h"
  19. #include "gpio.h"
  20. #include <avr/interrupt.h>
  22. extern bool    playing_note;
  23. extern bool    playing_melody;
  24. extern uint8_t note_timbre;
  26. #define CPU_PRESCALER 8
  28. /*
  29.   Audio Driver: PWM
  31.   drive up to two speakers through the AVR PWM hardware-peripheral, using timer1 and/or timer3 on Atmega32U4.
  33.   the primary channel_1 can be connected to either pin PC4 PC5 or PC6 (the later being used by most AVR based keyboards) with a PMW signal generated by timer3
  34.   and an optional secondary channel_2 on either pin PB5, PB6 or PB7, with a PWM signal from timer1
  36.   alternatively, the PWM pins on PORTB can be used as only/primary speaker
  37. */
  39. #if defined(AUDIO_PIN) && (AUDIO_PIN != C4) && (AUDIO_PIN != C5) && (AUDIO_PIN != C6) && (AUDIO_PIN != B5) && (AUDIO_PIN != B6) && (AUDIO_PIN != B7) && (AUDIO_PIN != D5)
  40. #    error "Audio feature enabled, but no suitable pin selected as AUDIO_PIN - see docs/feature_audio under the AVR settings for available options."
  41. #endif
  43. #if (AUDIO_PIN == C4) || (AUDIO_PIN == C5) || (AUDIO_PIN == C6)
  44. #    define AUDIO1_PIN_SET
  45. #    define AUDIO1_TIMSKx TIMSK3
  46. #    define AUDIO1_TCCRxA TCCR3A
  47. #    define AUDIO1_TCCRxB TCCR3B
  48. #    define AUDIO1_ICRx ICR3
  49. #    define AUDIO1_WGMx0 WGM30
  50. #    define AUDIO1_WGMx1 WGM31
  51. #    define AUDIO1_WGMx2 WGM32
  52. #    define AUDIO1_WGMx3 WGM33
  53. #    define AUDIO1_CSx0 CS30
  54. #    define AUDIO1_CSx1 CS31
  55. #    define AUDIO1_CSx2 CS32
  57. #    if (AUDIO_PIN == C6)
  58. #        define AUDIO1_COMxy0 COM3A0
  59. #        define AUDIO1_COMxy1 COM3A1
  60. #        define AUDIO1_OCIExy OCIE3A
  61. #        define AUDIO1_OCRxy OCR3A
  62. #        define AUDIO1_PIN C6
  63. #        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPA_vect
  64. #    elif (AUDIO_PIN == C5)
  65. #        define AUDIO1_COMxy0 COM3B0
  66. #        define AUDIO1_COMxy1 COM3B1
  67. #        define AUDIO1_OCIExy OCIE3B
  68. #        define AUDIO1_OCRxy OCR3B
  69. #        define AUDIO1_PIN C5
  70. #        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPB_vect
  71. #    elif (AUDIO_PIN == C4)
  72. #        define AUDIO1_COMxy0 COM3C0
  73. #        define AUDIO1_COMxy1 COM3C1
  74. #        define AUDIO1_OCIExy OCIE3C
  75. #        define AUDIO1_OCRxy OCR3C
  76. #        define AUDIO1_PIN C4
  77. #        define AUDIO1_TIMERx_COMPy_vect TIMER3_COMPC_vect
  78. #    endif
  79. #endif
  81. #if defined(AUDIO_PIN) && defined(AUDIO_PIN_ALT) && (AUDIO_PIN == AUDIO_PIN_ALT)
  82. #    error "Audio feature: AUDIO_PIN and AUDIO_PIN_ALT on the same pin makes no sense."
  83. #endif
  85. #if ((AUDIO_PIN == B5) && ((AUDIO_PIN_ALT == B6) || (AUDIO_PIN_ALT == B7))) || ((AUDIO_PIN == B6) && ((AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B7))) || ((AUDIO_PIN == B7) && ((AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B6)))
  86. #    error "Audio feature: PORTB as AUDIO_PIN and AUDIO_PIN_ALT at the same time is not supported."
  87. #endif
  89. #if defined(AUDIO_PIN_ALT) && (AUDIO_PIN_ALT != B5) && (AUDIO_PIN_ALT != B6) && (AUDIO_PIN_ALT != B7)
  90. #    error "Audio feature: the pin selected as AUDIO_PIN_ALT is not supported."
  91. #endif
  93. #if (AUDIO_PIN == B5) || (AUDIO_PIN == B6) || (AUDIO_PIN == B7) || (AUDIO_PIN_ALT == B5) || (AUDIO_PIN_ALT == B6) || (AUDIO_PIN_ALT == B7) || (AUDIO_PIN == D5)
  94. #    define AUDIO2_PIN_SET
  95. #    define AUDIO2_TIMSKx TIMSK1
  96. #    define AUDIO2_TCCRxA TCCR1A
  97. #    define AUDIO2_TCCRxB TCCR1B
  98. #    define AUDIO2_ICRx ICR1
  99. #    define AUDIO2_WGMx0 WGM10
  100. #    define AUDIO2_WGMx1 WGM11
  101. #    define AUDIO2_WGMx2 WGM12
  102. #    define AUDIO2_WGMx3 WGM13
  103. #    define AUDIO2_CSx0 CS10
  104. #    define AUDIO2_CSx1 CS11
  105. #    define AUDIO2_CSx2 CS12
  107. #    if (AUDIO_PIN == B5) || (AUDIO_PIN_ALT == B5)
  108. #        define AUDIO2_COMxy0 COM1A0
  109. #        define AUDIO2_COMxy1 COM1A1
  110. #        define AUDIO2_OCIExy OCIE1A
  111. #        define AUDIO2_OCRxy OCR1A
  112. #        define AUDIO2_PIN B5
  113. #        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPA_vect
  114. #    elif (AUDIO_PIN == B6) || (AUDIO_PIN_ALT == B6)
  115. #        define AUDIO2_COMxy0 COM1B0
  116. #        define AUDIO2_COMxy1 COM1B1
  117. #        define AUDIO2_OCIExy OCIE1B
  118. #        define AUDIO2_OCRxy OCR1B
  119. #        define AUDIO2_PIN B6
  120. #        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPB_vect
  121. #    elif (AUDIO_PIN == B7) || (AUDIO_PIN_ALT == B7)
  122. #        define AUDIO2_COMxy0 COM1C0
  123. #        define AUDIO2_COMxy1 COM1C1
  124. #        define AUDIO2_OCIExy OCIE1C
  125. #        define AUDIO2_OCRxy OCR1C
  126. #        define AUDIO2_PIN B7
  127. #        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPC_vect
  128. #    elif (AUDIO_PIN == D5) && defined(__AVR_ATmega32A__)
  129. #        pragma message "Audio support for ATmega32A is experimental and can cause crashes."
  130. #        undef AUDIO2_TIMSKx
  131. #        define AUDIO2_TIMSKx TIMSK
  132. #        define AUDIO2_COMxy0 COM1A0
  133. #        define AUDIO2_COMxy1 COM1A1
  134. #        define AUDIO2_OCIExy OCIE1A
  135. #        define AUDIO2_OCRxy OCR1A
  136. #        define AUDIO2_PIN D5
  137. #        define AUDIO2_TIMERx_COMPy_vect TIMER1_COMPA_vect
  138. #    endif
  139. #endif
  141. // C6 seems to be the assumed default by many existing keyboard - but sill warn the user
  142. #if !defined(AUDIO1_PIN_SET) && !defined(AUDIO2_PIN_SET)
  143. #    pragma message "Audio feature enabled, but no suitable pin selected - see docs/feature_audio under the AVR settings for available options. Don't expect to hear anything... :-)"
  144. // TODO: make this an error - go through the breaking-change-process and change all keyboards to the new define
  145. #endif
  146. // -----------------------------------------------------------------------------
  148. #ifdef AUDIO1_PIN_SET
  149. static float channel_1_frequency = 0.0f;
  150. void         channel_1_set_frequency(float freq) {
  151.     if (freq == 0.0f) // a pause/rest is a valid "note" with freq=0
  152.     {
  153.         // disable the output, but keep the pwm-ISR going (with the previous
  154.         // frequency) so the audio-state keeps getting updated
  155.         // Note: setting the duty-cycle 0 is not possible on non-inverting PWM mode - see the AVR data-sheet
  156.         AUDIO1_TCCRxA &= ~(_BV(AUDIO1_COMxy1) | _BV(AUDIO1_COMxy0));
  157.         return;
  158.     } else {
  159.         AUDIO1_TCCRxA |= _BV(AUDIO1_COMxy1); // enable output, PWM mode
  160.     }
  162.     channel_1_frequency = freq;
  164.     // set pwm period
  165.     AUDIO1_ICRx = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER));
  166.     // and duty cycle
  167.     AUDIO1_OCRxy = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre / 100);
  168. }
  170. void channel_1_start(void) {
  171.     // enable timer-counter ISR
  172.     AUDIO1_TIMSKx |= _BV(AUDIO1_OCIExy);
  173.     // enable timer-counter output
  174.     AUDIO1_TCCRxA |= _BV(AUDIO1_COMxy1);
  175. }
  177. void channel_1_stop(void) {
  178.     // disable timer-counter ISR
  179.     AUDIO1_TIMSKx &= ~_BV(AUDIO1_OCIExy);
  180.     // disable timer-counter output
  181.     AUDIO1_TCCRxA &= ~(_BV(AUDIO1_COMxy1) | _BV(AUDIO1_COMxy0));
  182. }
  183. #endif
  185. #ifdef AUDIO2_PIN_SET
  186. static float channel_2_frequency = 0.0f;
  187. void         channel_2_set_frequency(float freq) {
  188.     if (freq == 0.0f) {
  189.         AUDIO2_TCCRxA &= ~(_BV(AUDIO2_COMxy1) | _BV(AUDIO2_COMxy0));
  190.         return;
  191.     } else {
  192.         AUDIO2_TCCRxA |= _BV(AUDIO2_COMxy1);
  193.     }
  195.     channel_2_frequency = freq;
  197.     AUDIO2_ICRx  = (uint16_t)(((float)F_CPU) / (freq * CPU_PRESCALER));
  198.     AUDIO2_OCRxy = (uint16_t)((((float)F_CPU) / (freq * CPU_PRESCALER)) * note_timbre / 100);
  199. }
  201. float channel_2_get_frequency(void) {
  202.     return channel_2_frequency;
  203. }
  205. void channel_2_start(void) {
  206.     AUDIO2_TIMSKx |= _BV(AUDIO2_OCIExy);
  207.     AUDIO2_TCCRxA |= _BV(AUDIO2_COMxy1);
  208. }
  210. void channel_2_stop(void) {
  211.     AUDIO2_TIMSKx &= ~_BV(AUDIO2_OCIExy);
  212.     AUDIO2_TCCRxA &= ~(_BV(AUDIO2_COMxy1) | _BV(AUDIO2_COMxy0));
  213. }
  214. #endif
  216. void audio_driver_initialize_impl(void) {
  217. #ifdef AUDIO1_PIN_SET
  218.     channel_1_stop();
  219.     gpio_set_pin_output(AUDIO1_PIN);
  220. #endif
  222. #ifdef AUDIO2_PIN_SET
  223.     channel_2_stop();
  224.     gpio_set_pin_output(AUDIO2_PIN);
  225. #endif
  227.     // TCCR3A / TCCR3B: Timer/Counter #3 Control Registers TCCR3A/TCCR3B, TCCR1A/TCCR1B
  228.     // Compare Output Mode (COM3An and COM1An) = 0b00 = Normal port operation
  229.     //   OC3A -- PC6
  230.     //   OC3B -- PC5
  231.     //   OC3C -- PC4
  232.     //   OC1A -- PB5
  233.     //   OC1B -- PB6
  234.     //   OC1C -- PB7
  236.     // Waveform Generation Mode (WGM3n) = 0b1110 = Fast PWM Mode 14. Period = ICR3, Duty Cycle OCR3A)
  237.     //   OCR3A - PC6
  238.     //   OCR3B - PC5
  239.     //   OCR3C - PC4
  240.     //   OCR1A - PB5
  241.     //   OCR1B - PB6
  242.     //   OCR1C - PB7
  244.     // Clock Select (CS3n) = 0b010 = Clock / 8
  245. #ifdef AUDIO1_PIN_SET
  246.     // initialize timer-counter
  247.     AUDIO1_TCCRxA = (0 << AUDIO1_COMxy1) | (0 << AUDIO1_COMxy0) | (1 << AUDIO1_WGMx1) | (0 << AUDIO1_WGMx0);
  248.     AUDIO1_TCCRxB = (1 << AUDIO1_WGMx3) | (1 << AUDIO1_WGMx2) | (0 << AUDIO1_CSx2) | (1 << AUDIO1_CSx1) | (0 << AUDIO1_CSx0);
  249. #endif
  251. #ifdef AUDIO2_PIN_SET
  252.     AUDIO2_TCCRxA = (0 << AUDIO2_COMxy1) | (0 << AUDIO2_COMxy0) | (1 << AUDIO2_WGMx1) | (0 << AUDIO2_WGMx0);
  253.     AUDIO2_TCCRxB = (1 << AUDIO2_WGMx3) | (1 << AUDIO2_WGMx2) | (0 << AUDIO2_CSx2) | (1 << AUDIO2_CSx1) | (0 << AUDIO2_CSx0);
  254. #endif
  255. }
  257. void audio_driver_stop_impl(void) {
  258. #ifdef AUDIO1_PIN_SET
  259.     channel_1_stop();
  260. #endif
  262. #ifdef AUDIO2_PIN_SET
  263.     channel_2_stop();
  264. #endif
  265. }
  267. void audio_driver_start_impl(void) {
  268. #ifdef AUDIO1_PIN_SET
  269.     channel_1_start();
  270.     if (playing_note) {
  271.         channel_1_set_frequency(audio_get_processed_frequency(0));
  272.     }
  273. #endif
  275. #if !defined(AUDIO1_PIN_SET) && defined(AUDIO2_PIN_SET)
  276.     channel_2_start();
  277.     if (playing_note) {
  278.         channel_2_set_frequency(audio_get_processed_frequency(0));
  279.     }
  280. #endif
  281. }
  283. static volatile uint32_t isr_counter = 0;
  284. #ifdef AUDIO1_PIN_SET
  285. ISR(AUDIO1_TIMERx_COMPy_vect) {
  286.     isr_counter++;
  287.     if (isr_counter < channel_1_frequency / (CPU_PRESCALER * 8)) return;
  289.     isr_counter        = 0;
  290.     bool state_changed = audio_update_state();
  292.     if (!playing_note && !playing_melody) {
  293.         channel_1_stop();
  294. #    ifdef AUDIO2_PIN_SET
  295.         channel_2_stop();
  296. #    endif
  297.         return;
  298.     }
  300.     if (state_changed) {
  301.         channel_1_set_frequency(audio_get_processed_frequency(0));
  302. #    ifdef AUDIO2_PIN_SET
  303.         if (audio_get_number_of_active_tones() > 1) {
  304.             channel_2_set_frequency(audio_get_processed_frequency(1));
  305.         } else {
  306.             channel_2_stop();
  307.         }
  308. #    endif
  309.     }
  310. }
  311. #endif
  313. #if !defined(AUDIO1_PIN_SET) && defined(AUDIO2_PIN_SET)
  314. ISR(AUDIO2_TIMERx_COMPy_vect) {
  315.     isr_counter++;
  316.     if (isr_counter < channel_2_frequency / (CPU_PRESCALER * 8)) return;
  318.     isr_counter        = 0;
  319.     bool state_changed = audio_update_state();
  321.     if (!playing_note && !playing_melody) {
  322.         channel_2_stop();
  323.         return;
  324.     }
  326.     if (state_changed) {
  327.         channel_2_set_frequency(audio_get_processed_frequency(0));
  328.     }
  329. }
  330. #endif